I heard that you can use action replay codes in Pokemon Platinum, but every time I put a code in, nothing happens.
I follow what to do after enterting the code, such as: hold L/R or stuff like that...
Am i doing something wrong? Does anyone know working codes?
That FAQ article refers to RAW cheats, not action replay codes, Shash.
Regarding the codes - either the code is wrong, either the code wasn't made for your version of the game, or the emulator isn't doing what it's supposed to do with the code.